Question 593604
What we know:<br/>

(I):&nbsp;{{{tan(theta) = sin(theta)/cos(theta)}}}
(II):&nbsp;{{{tan(theta) = -sqrt(3)/3}}}
(III):&nbsp;{{{sin(theta) = 1/2}}}
(IV):&nbsp;{{{cos(theta)*sec(theta) = 1}}}
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From (I)+(II)+(III) => {{{cos(theta) = -sqrt(3)/2}}}  (**)
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From(**)+(IV) => {{{sec(theta) = -2*sqrt(3)/3}}}